n = int(input())
c = input()
cnt = [0 for _ in range(n)]
red = 0
for i in range(n):
   if c[i] == 'R': red += 1
   cnt[i] = red

print(red - cnt[red-1]) n = int(input()) n int(input()) int input() input c = input() c input() input 0 for _ in range(n) for _ in range(n) _ range(n) range n for _ in range(n) 0 cnt = [0 for _ in range(n)] cnt [0 for _ in range(n)] red = 0 red 0 for i in range(n):
   if c[i] == 'R': red += 1
   cnt[i] = red i range(n) range n if c[i] == 'R': red += 1
    c[i] == 'R' c[i] c i 'R' cnt[i] = red cnt[i] cnt i red print(red - cnt[red-1]) print red - cnt[red-1] red cnt[red-1] cnt red-1 red 1 n = int(input()) int(input()) n red = 0 0 red cnt = [0 for _ in range(n)] [0 for _ in range(n)] cnt c = input() input() c
n = int(input())
c = input()
cnt = [0 for _ in range(n)]
red = 0
for i in range(n):
   if c[i] == 'R': red += 1
   cnt[i] = red

print(red - cnt[red-1])